December in Karlshamn is the rainiest and the windiest month of the year. In December, the weather in Karlshamn is typically cold. Average daily high temperature in December is about 3 degrees above zero. On average, Karlshamn has 22 rainy, 7 cloudy, and 2 sunny days in December. The rains are usually light. December as well as January, February, and November is considered the most uncomfortable time to visit Karlshamn.